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Grayscale PDF
Turn colours into gray — saves ink when printing. Free, no sign-up, nothing to install. Files are processed on your own device — never uploaded to a server.
How to use Grayscale PDF
- 1
Open DinoRexPDF in the browser on your computer.
- 2
Choose or drag in your files. They are processed on your own device, not uploaded.
- 3
Finish your edits, then click Save to download the result.
Why DinoRexPDF?
Never touches the cloud
Files travel straight from phone to laptop over your own Wi-Fi.
No install, no account
Just a browser. No sign-up, no installation.
As fast as your Wi-Fi
No uploading or downloading. Big files move in seconds.
App-grade scanner
Edges detected automatically, perspective straightened, paper clean white.
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